Annealing-furnace.



J. A. & J. C. S'WINDELL.

ANNEALING FURNAGE.

APPLICATION FILED 11110.12,1o13.`

1,1 12,237. Patented Sept. 29, 1914.

Z SHEETS-SHEET 1.

THE KORRIS PETERS CO., PHTU-LITHO., WASHINGTON, DA C.

J. A. & J. C. SWINDELL.

ANNEALING PURNACE.

APPLICATION FILED DEG.12,1913.

NVENTOR5 2 SHEETS-SHEET 2.

Patented Sept. 29, 1914.

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THE MORRIS PETERS CO., PHOTO-LITHO.. WASHING roN, D. C.

UNTTED sTATEs PATENT OEEIOE.

JOHN ALBERT sWINnELL AND JOHN o. sWINDELL, or PITTSBURGH, PENNSYLVANIA.

ANNEALINGFURNACE. y

Specification of Letters Patent. Patellltedsept. 29, 1914.`

Application filed December 12, 1913. Serial No. 806,225.

To all whom it may concern i Be it known that we, JOHN `A. SWINDELL and JOHN C. SWINDELL, both citizens of the United States, and both residing at Pittsburgh, in the the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Annealing-F urnaces, of which the following is a full, clear,-

and exact description, reference being had to the accompanying drawings, forming part of this specication, in which- Figure l is a sectional perspective view of one form of furnace embodying our invention; Fig. 2 is a transverse vertical section of another form of furnace embodying our invention; and Figs. 3 and 4l are `hori-` zontal sections, taken respectively on the lines HI-III and IV--TV Of Figs. l and 2.

Our invention has relation to annealing furnaces, and more particularly to furnaces of the general character described and claimed in the patent to William A. and John C. Swindell, No. 624,401 of` May 2, 1899.

The object of the present invention is to provide a furnace which will possess the well known advantages of Vfurnaces constructed in accordance with the said patent and which have gone into extensive commercial use,

together with addedadvantages which still further increase the efficiency of the furnace.

An especial Object of the invention is to Y provide for a better and more eilicient combustion of the fuel gas by providing means of novel character and arrangement whereby the air and gas in passing to the point of combustion are preheated to a high degree.

In the accompanying drawings, we have shown our invention as applied to two different forms of furnaces in which the combustion takes place at the central portion of the furnace and the ames and products of combustion pass laterally in opposite directions toward the sides of the annealing chamber and over a row of annealing boxes placed at each side of saidv chamber. After passing over the annealing boxes, the prod ucts of combustion pass downwardly into longitudinally arrangedwaste fiues which carry them to the stack. These waste flues,

together with the air and gas supply fines,

are all arranged longitudinally in the base of the furnace and in such a manner that the air and gas become preheated to a very great extentbefore meeting. This general arrangement is not, however, claimed in the present case, but forms the subject matter vof a co-pending application by John Albert Swindell, one of the applicants herein. The

novel subject matter of the present appli cation has a reference to a further preheatving of the air and gas.

Referring to the accompanying drawinsf-f and first` to the construction of furnace shown in Figs. l and 8, the numeral 2 designates the vwall of the furnace having the base 3 and inclosiug above said base portion an `annealing chamber l.

chamber is provided at each side of the center with a suitable supporting surface 5 for the usual annealing boxes which are placed end to end. Formed inthe base 3 of the furnace are the longitudinally extending waste fiues 6 and 6, the longitudinally extending air flues 7, andthe central longitudinally extending gas supply flue 8. The waste and air flues are duplicated for each side of the furnace. The waste flues `are shown as doublefpass lues (see Fig. 3), the two passes 6 and 6a of each flue being connected at one end as shown. Each air flue 7 is arranged between the two passes of a waste flue; and the central gasflue 8 is arranged between the passes 6a ofthe two waste flues. Inasmuch as these furnaces are operated at relatively high temperatures for considerable periods of time, the entire base of the furnace becomes highly heated, not only by conduction throughthe base from the annealing chamber, but also by conduction through the walls of the waste lues. The waste gases passing tothe stack are at a comparatively high temperature and a large amount of heat is thus available for conduction through `these walls. This conduction readily takes place owing to the fact that the walls of the air `flues are being constantly cooled by` the entrance of air at atmospheric temperature. It will therefore be apparent that both the air and the gas will be preheated to a very considerable degree in passing through these iues.

`The two parts of the annealing chamber are separated at their lower'portions by a central longitudinal wall 9. ln accordance with our present'invention,this wall is made hollow to inclose and contain a central longitudinal air preheating chamber 10 extending down into the base 3 immediately above the roof'arch of the gas Hue 8." The air flues 7 `communicate with this chamber l0 by This annealing` a series of oblique transverse ports 11. The upper portion of the chamber has at each side a series of discharge openings 12. lVe also provide the central portion of the furnace with the baille walls 13, one at each side of thecentral wall 9. The upper edges of v the I'baffle walls terminate 'at about the level of the bottoms of the disch arge openings 12. Extending upwardly from the gas flue 8 are two series `of vertical ports 1li and 15, these ports leading to the continuous chambers 111a and 15L which extend to the upper edges of the'said baffle walls and are arranged to discharge g'as adjacent to the openings 12. The two'series of ports 14 and 15 are in staggered relation to each other; and the two sets of air ports 11 are also staggered so that there lisan alternating arrangement of. gas and air ports at each side.

It will be Vreadily understood that the wallsrof the-'central chamber 1() will become highly heated in the operation of the furfnace, andthat thereby vthe air delivered into such chamber by the ports 11 will also be raised -to a comparatively high temperature. The fgas flowing upwardly through the ports ll-and 15 'also has its temperature increased. Therefore, when the air land gas meet adjacent to fthe upper Vedges of the battles 13, both air andfgas are'at relatively high temperatures and a very high degree of comb-ustion takes place.

IIn Figs. 2 and l we have shown our inventio'n applied in asomewhat modified form and to-a somewhatdiiferently arranged furnace. .In this furnace each waste flue 16 is asingle-.pass flue and each air flue has the Y double fpasses 17 and 17 a, the-air first entering the pass 17 -of each flue and then going into the pass 17 a. 18 is the central gas supplyiiue. Each Spass 17 a of theair ilues communicates with the chamber 19 in the cenl'tral wall -20 by means of the ports 21 waich correspond to the `ports 11 of the furnace first described. The gas flue 1S communicate's'with-this centralchamber 19 bya series -of vvertical ports 22. The upper portion of the side -walls of the-chamber 19 are provided with the discharge perforations 23 preferably arranged at different levels and discharging linto chambers 24- behind the longitudinal baffle walls 25. In this form it will Vbe-'seen that the air and gas are brought together'in the chamber v19, but withsubstantially the same degree of preheating as in the form first described. Not only are the Walls ofthe chamber-2O at a very high temperaturabut the baille walls 25 arealso, of course,vata high temperatura-so that combustiontakes place under the most favorable conditions. Y

lIn both forms of furnace shown and described, -the 'ch-amber4lis, in effect, divided into two chambers or compartments; and

eaehchamber -or compartment may -be operated independently to or at a different temperature from the other chamber or compartment. The wall at that side of each chamber or compartment which has the inlet ports may be of any desired height.

lt will be readily understood that our invention is not limited in its application to furnaces of the general construction and arrangement of air, gas and waste lines such as shown and described. In all cases, however, we prefer to employ our invention in connection with a .longitudinal parallel arrangement of such flues located in the base of the furnace in such a manner that the gas and air will be preheated in passing through it and can be readily brought together at the central portion of the furnace where further preheating in accordance with our invention takes place prior to and at the time of combustion.

By the term preheating chamber as used in the claims, we desire to cover either an air chamber, such as the chamber 10 of Fig. 1, or a combined air and gas chamber, such as that shown at 2O in Fig. 2.

lVhile our invention is particularly applicable to annealing furnaces it may also be applied to other heating furnaces.

What we claim is:

1. A furnace of the character described having longitudinally extending gas and air supply iues in its base and having a centrally arranged longitudinal preheating chamber extending downwardly within the base of the furnace, and with which said air flue communicates, said chamber having discharge openings at its upper portion, and means for delivering gas from the gas sup* ply flue to be mixed and burned with said air; substantially as described.

2. A furnace of the character described having a` hollow central wall extending upwardly within the lower portion of the fur nace chamber and containing therein a preheating chamber, said Vall having discharge openings leading outwardly therefrom into said chamber, means for delivering air into the said preheating chamber, and mea-ns for supplying gas to be burned with said air, said means comprising a iiue extending longitudinally within the base of the furnace below the said wall, and having upwardly extending ports, and said furnace chamber having oii'talre means for thelproducts of combustion extending along its opposite side throughout substantially the entire length thereof.

3. A.y furnace of the character described having a hollow central longitudinal wall projecting upwardly into the lower portion of vits furnace chamber, said wall inclosing a preheating chamber having openings leading outwardly therefrom into the furnace chamber, a longitudinally extending baille wall adjacent to said hollow central wall,

means for delivering air into the said pre heating chamber, and means for supplying gas to be burned with the air preheated in said preheating chamber; substantially as described.

1l. A furnace of the character described having in its base longitudinally arranged Waste ports communicating with the opposite sides of the furnace chamber and also having in its base longitudinally arranged air and gas supply ports Whose Walls are arranged to be heated by conduction from the waste ports, said furnace also having a cen trally arranged preheatinp' chamber communicating with the air lines and having discharge openings at opposite sides of its upper portion within the furnace chamber, and connections leading from the gas port to supply gas to be burned with the air preheated in said chamber; substantially as described.

5. A. furnace of the character' described having its base provided with waste, air and gas ports, the walls of the air and: gas ports beingarranged to be heated by conduction from the furnace chamber and also by conduction from the waste ports, and also having at itscentral portion air and gas heatingpassages connected respectively with the said air .and gas ports; substantially as described.

6. A furnace of the character described, having `a heating chamber or compartment with a hollow wall at the lower portion of one side thereof, said wall containing a preheating chamber, the base of the furnace having therein a longitudinally extending air flue which is connected with said preheating chamber,and the latter having outlets `into the heatingchamber or compartment, a longitudinally extending baffle Wall adjacent to said hollow` Wall but spaced laterally therefrom, and means for supplying gas to be burned with the air; substantially as described.

In testimony whereof, we have hereunto set our hands.

JOHN ALBERT SWINDELL. JOHN C. SWINDELL. Witnesses:

GEO. H. PARMELEE, H. M. CORWIN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

l Washington, D. G. 

